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S L Rauch

Publications and source records attributed to S L Rauch.

At least 37 records · Page 2Linked to original sources
PubMed2000

Schizophrenic subjects show aberrant fMRI activation of dorsolateral prefrontal cortex and basal ganglia during working memory performance.

BACKGROUND: Working memory (WM) deficits in schizophrenia have been associated with dorsolateral prefrontal cortex (DLPFC) dysfunction in neuroimaging studies. We previously found increased DLPFC activation in schizophrenic versus normal subjects during WM performance (Manoach et al 1999b). We now have investigated whether schizophrenic subjects recruit different brain regions, particularly the basal ganglia and thalamus, components of frontostriatal circuitry thought to mediate WM. METHODS: We examined regional brain activation in nine normal and nine schizophrenic subjects during WM performance using functional magnetic resonance imaging. Subjects performed a modified version of the Sternberg Item Recognition Paradigm that included a monetary reward for correct responses. We compared high and low WM load conditions to each other and to a non-WM baseline condition. We examined activation in both individual subjects and averaged group data. RESULTS: Relative to normal subjects, schizophrenic subjects exhibited deficient WM performance, at least an equal magnitude of right DLPFC activation, significantly greater left DLPFC activation, and increased spatial heterogeneity of DLPFC activation. Furthermore, only the schizophrenic group activated the basal ganglia and thalamus, even when matched for task performance with the normal group. CONCLUSIONS: Aberrant WM performance and brain activation in schizophrenia may reflect dysfunction of frontostriatal circuitry that subserves WM. Future studies will elucidate the contribution of the anatomical components of this circuitry to WM deficits.

Adult↗
PubMed2000

Activation of anterior paralimbic structures during guilt-related script-driven imagery.

BACKGROUND: Several recent neuroimaging studies have examined the neuroanatomical correlates of normal emotional states, such as happiness, sadness, fear, anger, anxiety, and disgust; however, no previous study has examined the emotional state of guilt. METHODS: In the current study, we used positron emission tomography and the script-driven imagery paradigm to study regional cerebral blood flow (rCBF) during the transient emotional experience of guilt in eight healthy male participants. In the Guilt condition, participants recalled and imagined participating in a personal event involving the most guilt they had ever experienced. In the Neutral condition, participants recalled and imagined participating in an emotionally neutral personal event. RESULTS: In the Guilt versus Neutral comparison, rCBF increases occurred in anterior paralimbic regions of the brain: bilateral anterior temporal poles, anterior cingulate gyrus, and left anterior insular cortex/inferior frontal gyrus. CONCLUSIONS: These results, along with those of previous studies, are consistent with the notion that anterior paralimbic regions of the brain mediate negative emotional states in healthy individuals.

Adult↗
PubMed2000

Exaggerated amygdala response to masked facial stimuli in posttraumatic stress disorder: a functional MRI study.

BACKGROUND: Converging lines of evidence have implicated the amygdala in the pathophysiology of posttraumatic stress disorder (PTSD). We previously developed a method for measuring automatic amygdala responses to general threat-related stimuli; in conjunction with functional magnetic resonance imaging, we used a passive viewing task involving masked presentations of human facial stimuli. METHODS: We applied this method to study veterans with PTSD and a comparison cohort of combat-exposed veterans without PTSD. RESULTS: The findings indicate that patients with PTSD exhibit exaggerated amygdala responses to masked-fearful versus masked-happy faces. CONCLUSIONS: Although some previous neuroimaging studies of PTSD have demonstrated amygdala recruitment in response to reminders of traumatic events, this represents the first evidence for exaggerated amygdala responses to general negative stimuli in PTSD. Furthermore, by using a probe that emphasizes automaticity, we provide initial evidence of amygdala hyperresponsivity dissociated from the "top-down" influences of medial frontal cortex.

Amygdala↗
PubMed2000

Neuroanatomy of human appetitive function: A positron emission tomography investigation.

OBJECTIVE: The mediating neuroanatomy of human appetitive function is poorly understood. A state induction paradigm was employed, in conjunction with positron emission tomography, to test the hypothesis that limbic/paralimbic regions respond to the desirability of food stimuli. METHODS: Eight normal subjects were studied during each of three conditions, involving visual exposure to high-caloric food, low-caloric food, and nonfood stimuli. Subjective indices of hunger were measured via analog scales. RESULTS: Planned contrasts demonstrated significant increases in desire to eat and decreases in left temporoinsular cortical blood flow during the high-caloric versus control conditions. DISCUSSION: Results implicate the temporo-insular cortex in normal appetitive function, suggesting that activity within this region is associated with the desirability or valence of food stimuli, prior to ingestion. These data will provide a broad foundation for future studies of patients with eating disorders.

Adult↗
PubMed2000

The cognitive-affective neuroscience of obsessive-compulsive disorder.

There is substantial evidence that obsessive-compulsive disorder (OCD) is mediated by specific cortico-striatal- thalamic-cortical (CTSC) circuits. Here we discuss very recent publications that address the following questions: How does damage to CSTC circuitry come about?; What are the neurochemical systems involved in mediating this circuitry?; and What are the implications of such damage for understanding the pathogenesis and management of OCD? A cognitive-affective neuroscience perspective is helpful in advancing our understanding of the role of these circuits in OCD and the dysfunctional procedural strategies that appear to characterize this disorder. Furthermore, this model is becoming integrated with a range of data including brain imaging, genetic, immunologic, and neurochemical findings.

Affect↗
PubMed2000

Functional neuroimaging and the neuroanatomy of obsessive-compulsive disorder.

Functional neuroimaging studies have advanced the understanding of the brain mediation of OCD by orbitofrontal-subcortical circuitry, but much is still unknown. Phenotypic heterogeneity could account for many of the inconsistencies among previous neuroimaging studies of OCD. Current studies are seeking to find the neurobiological basis of OCD symptom subtypes and predictors of treatment response. Future studies combining genetics and basic neuroanatomic research with neuroimaging may clarify the cause and pathophysiology of OCD. Although many lines of evidence point to dysfunction of orbitofrontal-subcortical circuitry in patients with OCD, many questions remain unanswered. Some have suggested that orbitofrontal-subcortical hyperactivity in OCD may be the result of abnormal neuroanatomic development of these structures or a failure of pruning of neuronal connections between them, as occurs in normal development, but no postmortem neuroanatomic studies of OCD exist to delineate its pathophysiology. Interventions that directly alter the indirect-direct pathway balance within frontal-subcortical circuits will allow for direct testing of the pathophysiologic hypotheses presented here. The roles of various neurochemical systems in OCD are similarly unclear. Although an abundance of indirect evidence suggests serotonergic abnormalities in patients with OCD, no direct evidence demonstrates what those abnormalities are or whether they are primary or secondary phenomena in patients with OCD. Ongoing studies of 5-HT synthesis in the brains of patients with OCD may shed light on this question.

Brain↗
PubMed2000

Characteristics of memory dysfunction in body dysmorphic disorder.

Although body dysmorphic disorder (BDD) is receiving increasing empirical attention, very little is known about neuropsychological deficits in this disorder. The current study investigated the nature of memory dysfunction in BDD, including the relationship between encoding strategies and verbal and nonverbal memory performance. We evaluated 17 patients with BDD and 17 healthy controls using the Rey-Osterrieth Complex Figure Test (RCFT) and the California Verbal Learning Test (CVLT). BDD patients differed significantly from healthy controls on verbal and nonverbal learning and memory indices. Multiple regression analyses revealed that group differences in free recall were statistically mediated by deficits in organizational strategies in the BDD cohort. These findings are similar to patterns previously observed in obsessive-compulsive disorder (OCD), suggesting a potential relationship between OCD and BDD. Studies in both groups have shown that verbal and nonverbal memory deficits are affected by impaired strategic processing.

Adult↗
PubMed2000

Relation of factor-analyzed symptom dimensions of obsessive-compulsive disorder to personality disorders.

OBJECTIVE: To assess the relation between symptom dimensions of obsessive-compulsive disorder (OCD) and comorbid personality disorders (PDs). METHOD: The scores of 75 OCD outpatients on five previously identified symptom dimensions were entered into multiple regression models as predictors of: 1) the presence of any type of PD; 2) the number of PDs; 3) the presence of any cluster A, B or C PD; and 4) the presence of each individual PD. RESULTS: Twenty-eight patients (37.3%) met criteria for one or more PDs. High scores on the 'Hoarding' dimension were strongly related to the presence of any Axis II diagnosis, and to the number of PDs. Cluster C PDs (especially obsessive-compulsive and avoidant) had the highest partial correlations with 'Hoarding'. These results were independent of OCD symptom severity. CONCLUSION: Previous conflicting findings about the prevalence of certain PDs in OCD might be due in part to differences in the constitution of the particular patient groups studied.

Adolescent↗
PubMed2000

Strategic processing and episodic memory impairment in obsessive compulsive disorder.

There is evidence that nonverbal memory problems in obsessive compulsive disorder (OCD) are mediated by impaired strategic processing. Although many studies have found verbal memory to be normal in OCD, these studies did not use tests designed to stress organizational strategies. This study examined verbal and nonverbal memory performance in 33 OCD patients and 30 normal control participants with the Rey-Osterrieth Complex Figure Test and the California Verbal Learning Test. OCD patients were impaired on verbal and nonverbal measures of organizational strategy and free recall. Multiple regression modeling indicated that free recall problems in OCD were mediated by impaired organizational strategies used during learning trials. Therefore, verbal and nonverbal episodic memory deficits in OCD are affected by impaired strategic processing. Results are consistent with neurobiological models proposing frontal-striatal system dysfunction in OCD.

Adult↗
PubMed2000

Reliability and validity of a scoring system for measuring organizational approach in the Complex Figure Test.

The Rey-Osterrieth Complex Figure Test (RCFT) is a widely-used measure of visuospatial construction and nonverbal memory. One of the critical aspects of this test is that organizing the figure into meaningful perceptual units during copy enhances its subsequent free recall from memory. This study examined the psychometric properties of a new system for quantifying the organizational approach to the RCFT figure and compared it to another compatible scoring system. We investigated interrater reliability of both systems and explored the influences of copy organization and copy accuracy on immediate recall. Seventy-one participants meeting DSM-IV criteria for obsessive-compulsive disorder and 55 healthy control participants completed the copy and immediate free recall condition of the RCFT. Interrater reliability was evaluated by Kappa coefficients and Pearson correlations. The effects of copy organization and copy accuracy on immediate recall were evaluated using multiple regression analyses. Results indicated that the organizational approach could be assessed with high reliability using both scoring systems. Organization during copy was a strong predictor for subsequent free recall from memory using both approaches. Multiple regression analysis indicated that all organizational elements were not equally predictive of memory performance. This new system represents a very simple and reliable approach to scoring organization on the RCFT, since it requires the identification of only 5 figure components. These characteristics should contribute to its clinical utility.

Adult↗
PubMed2000

Volume reduction in the caudate nucleus following stereotactic placement of lesions in the anterior cingulate cortex in humans: a morphometric magnetic resonance imaging study.

OBJECT: The goal of this study was to test hypotheses regarding changes in volume in subcortical structures following anterior cingulotomy. METHODS: Morphometric magnetic resonance (MR) imaging methods were used to assess volume reductions in subcortical regions following anterior cingulate lesioning in nine patients. Magnetic resonance imaging data obtained before and 9 +/- 6 months following anterior cingulotomy were subjected to segmentation and subcortical parcellation. Significant volume reductions were predicted and found bilaterally within the caudate nucleus, but not in the amygdala, thalamus, lenticular nuclei, or hippocampus. Subcortical parcellation revealed that the volume reduction in the caudate nucleus was principally referrable to the body, rather than the head. Furthermore, the magnitude of volume reduction in the caudate body was significantly correlated with total lesion volume. CONCLUSIONS: Taken together, these findings implicate significant connectivity between a region of anterior cingulate cortex (ACC) lesioned during cingulotomy and the caudate body. This unique data set complements published findings in nonhuman primates, and advances our knowledge regarding patterns of cortical-subcortical connectivity involving the ACC in humans. Moreover, these findings indicate changes distant from the site of anterior cingulotomy lesions that may play a role in the clinical response to this neurosurgical procedure.

Adolescent↗
PubMed2000

Sensory phenomena in obsessive-compulsive disorder and Tourette's disorder.

BACKGROUND: Recent studies have suggested that obsessive-compulsive disorder (OCD) is a heterogeneous disorder with some forms related to tics and Tourette's disorder. The present study was undertaken to investigate the sensory phenomena in patients with OCD and/or Tourette's disorder to determine if these phenotypic features represent valid clinical indices for differentiating tic-related OCD from non-tic-related OCD. METHOD: We evaluated 20 adult outpatients with OCD, 20 with OCD plus Tourette's disorder, and 21 with Tourette's disorder, using a semistructured interview designed to assess several definitions of sensory phenomena reported in the literature. DSM-III-R criteria were used for the OCD and Tourette's disorder diagnoses. RESULTS: Sensory phenomena including bodily sensations, mental urges, and a sense of inner tension were significantly more frequent in the 2 Tourette's disorder groups when compared with the OCD alone group. Feelings of incompleteness and a need for things to be "just right" were reported more frequently in the OCD plus Tourette's disorder group compared with the other 2 groups. CONCLUSION: Sensory phenomena may be an important phenotypic measure for grouping patients along the OCD-Tourette's disorder spectrum. Sensory phenomena include bodily and mental sensations. Bodily sensations include focal or generalized body sensations (usually tactile, muscular-skeletal/visceral, or both) occurring either before or during the patient's performance of the repetitive behaviors. These sensations are more frequently found in patients with OCD plus Tourette's disorder than in patients with OCD alone. Mental sensations include urge only, energy release (mental energy that builds up and needs to be discharged), incompleteness, and just-right perceptions. They are all more frequently found in patients with OCD plus Tourette's disorder than in patients with OCD alone.

Adult↗
PubMed1999

Anger in healthy men: a PET study using script-driven imagery.

BACKGROUND: An understanding of the neurobiological basis of normal emotional processing is useful in formulating hypotheses regarding the pathophysiology of psychiatric illnesses. METHODS: This study examined the mediating functional neuroanatomy of anger in eight healthy men. Narrative scripts were developed from autobiographical information to induce anger and neutral states. The subjects imagined the content of the narrative scripts to induce anger during positron emission tomography to measure normalized regional cerebral blood flow (rCBF). Psychophysiologic responses and subjective ratings of emotional state were measured for each condition. Statistical parametric maps were constructed to reflect the Anger versus Neutral state contrast. RESULTS: Anger was associated with activation of the left orbitofrontal cortex, right anterior cingulate cortex affective division, and bilateral anterior temporal poles. CONCLUSIONS: These results suggest that the subjective experience of anger is associated with rCBF increases in anterior paralimbic regions of the brain.

Adult↗
PubMed1999

Neural activation during sexual and competitive arousal in healthy men.

To investigate the mediating neuroanatomy of positively valenced arousal, we used script-driven imagery in conjunction with positron emission tomography to measure relative regional cerebral blood flow (rCBF) during sexual and competitive arousal, as well as neutral comparison states. Subjects were eight healthy right-handed men. Psychophysiologic responses and subjective ratings confirmed that the desired state manipulations were achieved. Statistical parametric mapping revealed similar patterns of rCBF changes for both positively valenced arousal conditions: increases were found within anterior cingulate and anterior temporal cortex as well as the ventral globus pallidus; decreases were found within widespread heteromodal association areas. These results complement findings from studies of other normal and pathological emotional states, and provide new insights regarding the neural substrates of pleasurable arousal in healthy men.

Adult↗
PubMed1999

Anterior cingulate cortex dysfunction in attention-deficit/hyperactivity disorder revealed by fMRI and the Counting Stroop.

BACKGROUND: The anterior cingulate cognitive division (ACcd) plays a central role in attentional processing by: 1) modulating stimulus selection (i.e., focusing attention) and/or 2) mediating response selection. We hypothesized that ACcd dysfunction might therefore contribute to producing core features of attention-deficit/hyperactivity disorder (ADHD), namely inattention and impulsivity. ADHD subjects have indeed shown performance deficits on the Color Stroop, an attentional/cognitive interference task known to recruit the ACcd. Recently, the Counting Stroop, a Stroop-variant specialized for functional magnetic resonance imaging (fMRI), produced ACcd activation in healthy adults. In the present fMRI study, the Counting Stroop was used to examine the functional integrity of the ACcd in ADHD. METHODS: Sixteen unmedicated adults from two groups (8 with ADHD and 8 matched control subjects) performed the Counting Stroop during fMRI. RESULTS: While both groups showed an interference effect, the ADHD group, in contrast to control subjects, failed to activate the ACcd during the Counting Stroop. Direct comparisons showed ACcd activity was significantly higher in the control group. ADHD subjects did activate a frontostriatal-insular network, indicating ACcd hypoactivity was not caused by globally poor neuronal responsiveness. CONCLUSIONS: The data support a hypothesized dysfunction of the ACcd in ADHD.

Adolescent↗